An Efficient Recyclable Polymer Supported Palladium Catalyst for Suzuki Reaction in Water

Abstract

This work describes the development of an efficient and reusable heterogeneous polymer supported palladium catalyst for Suzuki reaction in water. This novel catalyst system was designed through monoethanolamine (MEA) modification of nitrile group in Polyacrylonitrile (PAN) followed by metal salt (PdCl2) complexation. The resulting polymer complex (mPAN‐Pd) was then successfully optimised as an efficient heterogeneous catalyst for Suzuki reaction under ligand free conditions. The supported catalyst provided excellent reactivity in the coupling reactions of a series of aryl halides with phenyl boronic acids under mild reaction condition. The reaction proceeded in presence of 2 mol % of mPAN‐Pd catalyst at 80 °C in water and the resulting products were isolated in moderate to excellent yields upto 98 %. Furthermore, this catalyst can be conveniently recovered by simple filtration and reused at least five times without an appreciable loss in its activity or Palladium leaching.

Palladium recovery from acidic solution with phenanthroline-based covalent organic polymers as adsorbents for efficient heterogeneous catalysis

“…For comparison, some widely investigated palladium-based heterogeneous catalysts including COFs, MOFs, and the other types of materials for Suzuki–Miyaura cross-coupling reactions are listed in Table S7 †. Compared with other catalysts, although the TON/TOF is lower than some very efficient catalysts, it is still relatively higher than some reported materials such as PCN-160-Pd, 51 Pd@CITCF-500, 47 mPAN-Pd, 52 Pd@COF-QA, 53 and so on. More importantly, COP-2-Pd( ii ) exhibits obviously better reusability.…”

Recent Advancements in Continuous‐Flow Suzuki‐Miyaura Coupling Utilizing Immobilized Molecular Palladium Complexes

“…Hence, there is considerable interest in the development of efficient and reusable heterogeneous Pd catalysts. [10][11][12][13][14] In recent decades, switching the technologies of fine chemical synthesis from traditional batch reactors to flow systems, especially for the use of packed-bed reactors with heterogeneous catalysts, has surfaced as means to enhance the reaction efficiency, safety and environmental compatibility. [15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31] This is mainly due to the continuous collection of the desired product from the reactor outlet, eliminating the need for catalyst separation from the reaction mixture.…”

“…While homogeneous Pd catalysts have been extensively studied for their high activity and selectivity, they face challenges in catalyst recovery and reuse. Hence, there is considerable interest in the development of efficient and reusable heterogeneous Pd catalysts [10–14] . In recent decades, switching the technologies of fine chemical synthesis from traditional batch reactors to flow systems, especially for the use of packed‐bed reactors with heterogeneous catalysts, has surfaced as means to enhance the reaction efficiency, safety and environmental compatibility [15–31] .…”